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#include <cstdio>
#include <algorithm>
#include <vector>

using namespace std;

#define UL unsigned long
#define MOD(x) ((x) % 1000000007)

int main() {
  int n;
  vector<UL> tab;
  UL agg[300002];

  scanf("%d", &n);
  for (int i = 0; i < n; ++i) {
    int x;
    scanf("%d", &x);
    tab.push_back(x);
  }

  agg[0] = 1;
  for (int i = 0; i < n; ++i) {
    if (agg[i] == 0) {
      continue;
    }
    UL suma = 0;
    for (int j = i; j < n; ++j) {
      suma = MOD(suma + tab[j]);
      if (suma % 2 == 0) {
        agg[j+1] = MOD(agg[j+1] + agg[i]);
      }
    }
  }
  printf("%d\n", agg[n]);
}